The corona infection is over, but the symptoms are not over. A large US study shows how diverse long-term symptoms of Covid-19 are and what health problems most corona patients still suffer from after the illness.

The fact that a Sars-CoV-2 infection can be treacherous has been shown several times during the pandemic years – the symptoms do not end for everyone when the acute infection ends. One in five adults under the age of 65 who have contracted the coronavirus have had long-term health problems. In the case of people over the age of 65, it is even one in four. This is the result of a study by the US health authority Centers for Disease Control and Prevention (CDC).

Both older and younger former Covid patients have twice the risk of developing respiratory problems, lung problems or a pulmonary embolism later than non-infected people. Those over 65 are at greater risk than younger Covid patients of developing neurological diseases, kidney failure and a range of mental illnesses as a result of the corona infection. The most common complaints in both groups were respiratory problems and musculoskeletal pain, the study said.

Manifold ailments at Long Covid

In other studies and surveys, exhaustion is also given as the most common symptom weeks or months after the corona infection has been overcome. After the fourth week one speaks of Long Covid and after three months of Post Covid. The long-term effects of corona include a large number of complaints. In the CDC study, the scientists also found health problems in many organ systems, including the lungs, kidneys and heart. Disorders in the endocrine system, blood circulation, neurological problems, gastrointestinal diseases and psychiatric problems can also arise. “It is sobering to see that the results of this study reconfirm the breadth of organ dysfunction and the magnitude of the problem,” said Dr. Ziyad Al-Aly, Head of Research and Development at V.A. St. Louis Health Care System and a clinical epidemiologist at Washington University in St. Louis, told The New York Times. He was not involved in the CDC study.

For the study, the researchers used a database with medical records and analyzed the data of around 350,000 people who had been infected with Sars-CoV-2 for the study period from March 2020 to November 2021. The data was compared to a control group of more than 1.6 million people who had not contracted the coronavirus. 26 symptoms that could be related to Covid-19 were examined. Patients who suffered from one of the 26 symptoms in the previous year were excluded from the study because the researchers wanted to find out which health problems only occurred after the Sars-CoV-2 infection.

Millions of patients could get diabetes, heart or kidney disease

A direct comparison of the Covid-19 patients with the control group shows that 38 percent of the people infected with the coronavirus have developed at least one health complaint 30 to 365 days after the Sars-CoV-2 diagnosis. In the control group, on the other hand, it was 16 percent. According to the study, those over 65 have a higher risk of long Covid than younger corona patients: 45 percent of people who became infected with Covid-19 developed new health problems compared to 19 percent of the control group. Among the younger it was 35 percent compared to 19 percent among the unified people. Based on this data, the scientists calculated that almost 21 percent of younger Covid patients and almost 27 percent of those over 65 years old have developed health problems that could be attributed to Long Covid. Ziyad Al-Aly said the study results suggest potentially millions of people could develop diabetes, heart or kidney disease, and neurological problems. “These are lifelong conditions – certainly manageable, but not curable.”

Other studies also suggest that 20 to 30 percent of former Covid patients could develop long-term symptoms. The World Health Organization assumes that ten to 20 percent of people who have recovered from the original corona infection suffer from medium and long-term symptoms. The study authors of the CDC conclude: “If health problems occur after a Covid-19 infection, this could affect a patient’s ability to contribute to the world of work and economic consequences for Sars-CoV- 2 survivors and their families.” That could also put a strain on the health services. “Now that we are in possession of the knowledge that Covid-19 can lead to serious long-term consequences, we need to develop additional tools to reduce the risk of Long Covid,” said Ziyad Al-Aly.

The study authors point out the limitations of their study. Because they only used medical records from a specific database, the results may not be applicable to all adult US citizens. The researchers did not consider patients’ vaccination status, ethnicity, gender, or geographical location. The scientists also point out that the data does not take into account the most recent omicron variant. The study also did not identify which variant the individual patients were infected with.

Sources: CDC Study, New York Times, WHO